<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>标题</title>
    <style>
        div {
            color: red;
            font-size: 30px;
            background-color: gray;
            width: 200px;
            margin-left: auto;
            margin-right: auto;
        }
        a{
            text-decoration: none;
        }
        table{
            border: red 3px solid;
            border-collapse: collapse;
        }
        td{
            border: red 3px solid;
        }
        ul{
            list-style: none;
        }
    </style>
</head>
<body>
    <div>div标签1</div>
    <a href="https://www.baidu.com">百度</a><br/>
    <table>
        <tr>
            <td>1.1</td>
            <td>1.2</td>
            <td>1.3</td>
        </tr>
        <tr>
            <td>2.1</td>
            <td>2.2</td>
            <td>2.3</td>
        </tr>
        <tr>
            <td>3.1</td>
            <td>3.2</td>
            <td>3.3</td>
        </tr>
    </table><br/>
    <ul>
        <li>a</li>
        <li>b</li>
        <li>c</li>
        <li>d</li>
    </ul>
</body>
</html>